MediaWiki REL1_32
FileCacheBase.php
Go to the documentation of this file.
1<?php
29abstract class FileCacheBase {
30 protected $mKey;
31 protected $mType = 'object';
32 protected $mExt = 'cache';
33 protected $mFilePath;
34 protected $mUseGzip;
35 /* lazy loaded */
36 protected $mCached;
37
38 /* @todo configurable? */
39 const MISS_FACTOR = 15; // log 1 every MISS_FACTOR cache misses
40 const MISS_TTL_SEC = 3600; // how many seconds ago is "recent"
41
42 protected function __construct() {
43 global $wgUseGzip;
44
45 $this->mUseGzip = (bool)$wgUseGzip;
46 }
47
52 final protected function baseCacheDirectory() {
54
56 }
57
62 abstract protected function cacheDirectory();
63
68 protected function cachePath() {
69 if ( $this->mFilePath !== null ) {
70 return $this->mFilePath;
71 }
72
73 $dir = $this->cacheDirectory();
74 # Build directories (methods include the trailing "/")
75 $subDirs = $this->typeSubdirectory() . $this->hashSubdirectory();
76 # Avoid extension confusion
77 $key = str_replace( '.', '%2E', urlencode( $this->mKey ) );
78 # Build the full file path
79 $this->mFilePath = "{$dir}/{$subDirs}{$key}.{$this->mExt}";
80 if ( $this->useGzip() ) {
81 $this->mFilePath .= '.gz';
82 }
83
84 return $this->mFilePath;
85 }
86
91 public function isCached() {
92 if ( $this->mCached === null ) {
93 $this->mCached = file_exists( $this->cachePath() );
94 }
95
96 return $this->mCached;
97 }
98
103 public function cacheTimestamp() {
104 $timestamp = filemtime( $this->cachePath() );
105
106 return ( $timestamp !== false )
107 ? wfTimestamp( TS_MW, $timestamp )
108 : false;
109 }
110
117 public function isCacheGood( $timestamp = '' ) {
118 global $wgCacheEpoch;
119
120 if ( !$this->isCached() ) {
121 return false;
122 }
123
124 $cachetime = $this->cacheTimestamp();
125 $good = ( $timestamp <= $cachetime && $wgCacheEpoch <= $cachetime );
126 wfDebug( __METHOD__ .
127 ": cachetime $cachetime, touched '{$timestamp}' epoch {$wgCacheEpoch}, good $good\n" );
128
129 return $good;
130 }
131
136 protected function useGzip() {
137 return $this->mUseGzip;
138 }
139
144 public function fetchText() {
145 if ( $this->useGzip() ) {
146 $fh = gzopen( $this->cachePath(), 'rb' );
147
148 return stream_get_contents( $fh );
149 } else {
150 return file_get_contents( $this->cachePath() );
151 }
152 }
153
159 public function saveText( $text ) {
160 if ( $this->useGzip() ) {
161 $text = gzencode( $text );
162 }
163
164 $this->checkCacheDirs(); // build parent dir
165 if ( !file_put_contents( $this->cachePath(), $text, LOCK_EX ) ) {
166 wfDebug( __METHOD__ . "() failed saving " . $this->cachePath() . "\n" );
167 $this->mCached = null;
168
169 return false;
170 }
171
172 $this->mCached = true;
173
174 return $text;
175 }
176
181 public function clearCache() {
182 Wikimedia\suppressWarnings();
183 unlink( $this->cachePath() );
184 Wikimedia\restoreWarnings();
185 $this->mCached = false;
186 }
187
192 protected function checkCacheDirs() {
193 wfMkdirParents( dirname( $this->cachePath() ), null, __METHOD__ );
194 }
195
203 protected function typeSubdirectory() {
204 return $this->mType . '/';
205 }
206
212 protected function hashSubdirectory() {
213 global $wgFileCacheDepth;
214
215 $subdir = '';
216 if ( $wgFileCacheDepth > 0 ) {
217 $hash = md5( $this->mKey );
218 for ( $i = 1; $i <= $wgFileCacheDepth; $i++ ) {
219 $subdir .= substr( $hash, 0, $i ) . '/';
220 }
221 }
222
223 return $subdir;
224 }
225
232 if ( mt_rand( 0, self::MISS_FACTOR - 1 ) == 0 ) {
233 $cache = ObjectCache::getLocalClusterInstance();
234 # Get a large IP range that should include the user even if that
235 # person's IP address changes
236 $ip = $request->getIP();
237 if ( !IP::isValid( $ip ) ) {
238 return;
239 }
240 $ip = IP::isIPv6( $ip )
241 ? IP::sanitizeRange( "$ip/32" )
242 : IP::sanitizeRange( "$ip/16" );
243
244 # Bail out if a request already came from this range...
245 $key = $cache->makeKey( static::class, 'attempt', $this->mType, $this->mKey, $ip );
246 if ( $cache->get( $key ) ) {
247 return; // possibly the same user
248 }
249 $cache->set( $key, 1, self::MISS_TTL_SEC );
250
251 # Increment the number of cache misses...
252 $key = $this->cacheMissKey( $cache );
253 if ( $cache->get( $key ) === false ) {
254 $cache->set( $key, 1, self::MISS_TTL_SEC );
255 } else {
256 $cache->incr( $key );
257 }
258 }
259 }
260
265 public function getMissesRecent() {
266 $cache = ObjectCache::getLocalClusterInstance();
267
268 return self::MISS_FACTOR * $cache->get( $this->cacheMissKey( $cache ) );
269 }
270
275 protected function cacheMissKey( BagOStuff $cache ) {
276 return $cache->makeKey( static::class, 'misses', $this->mType, $this->mKey );
277 }
278}
$wgCacheEpoch
Set this to current time to invalidate all prior cached pages.
$wgFileCacheDepth
Depth of the subdirectory hierarchy to be created under $wgFileCacheDirectory.
$wgUseGzip
When using the file cache, we can store the cached HTML gzipped to save disk space.
$wgFileCacheDirectory
Directory where the cached page will be saved.
wfDebug( $text, $dest='all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
wfMkdirParents( $dir, $mode=null, $caller=null)
Make directory, and make all parent directories if they don't exist.
wfTimestamp( $outputtype=TS_UNIX, $ts=0)
Get a timestamp string in one of various formats.
Class representing a cache/ephemeral data store.
Definition BagOStuff.php:58
Base class for data storage in the file system.
isCacheGood( $timestamp='')
Check if up to date cache file exists.
useGzip()
Check if the cache is gzipped.
cachePath()
Get the path to the cache file.
saveText( $text)
Save and compress text to the cache.
fetchText()
Get the uncompressed text from the cache.
hashSubdirectory()
Return relative multi-level hash subdirectory (with trailing slash) or the empty string if not $wgFil...
getMissesRecent()
Roughly gets the cache misses in the last hour by unique visitors.
cacheDirectory()
Get the base cache directory (not specific to this file)
checkCacheDirs()
Create parent directors of $this->cachePath()
cacheTimestamp()
Get the last-modified timestamp of the cache file.
clearCache()
Clear the cache for this page.
typeSubdirectory()
Get the cache type subdirectory (with trailing slash) An extending class could use that method to alt...
cacheMissKey(BagOStuff $cache)
baseCacheDirectory()
Get the base file cache directory.
incrMissesRecent(WebRequest $request)
Roughly increments the cache misses in the last hour by unique visitors.
isCached()
Check if the cache file exists.
The WebRequest class encapsulates getting at data passed in the URL or via a POSTed form stripping il...
do that in ParserLimitReportFormat instead use this to modify the parameters of the image all existing parser cache entries will be invalid To avoid you ll need to handle that somehow(e.g. with the RejectParserCacheValue hook) because MediaWiki won 't do it for you. & $defaults also a ContextSource after deleting those rows but within the same transaction you ll probably need to make sure the header is varied on $request
Definition hooks.txt:2880
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition injection.txt:37
$cache
Definition mcc.php:33